Electric switch.



No. 649,554. Patented May l5, |900.

' F. SCHWEDTMANN.

ELECTRIC. SWITCH.

(Applxcation led Apr. 8, 1899 (No Model.) 3 Sheets-Sheet l.

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No. 649,554.A

F. SCHWEDTMANN.

ELECTRIC SWITCH.

(Application filed Apr. 8, 1899.)

3 Sheets--Sheet 2.

'.(No Model.)

Snow/tot wilma aseo F. Schwedtmann.

I @13 @Wol/nalga No. 649,554. Patented May I5, |900. F. SCHWEDTMANN.

ELECTRIC SWITCH.

, (Application led Apr. 8, 1899.)

(No Model.) 3 Sheds-Sheet 3.

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F. Schwedtmann 55% @Fiom/wij? A n Q ,HHM Mmmm 1w 3 Y m W Y 3 3 2 [WMM Ilm @Witnesses UNITED STATES PATENT FFICE.

FERDINAND scifiwnDrMANN, or sr. Louis, MissoURi;

LECTRIC swl'l-i.

srn'crrzrcArroN arming part of Letters Patent No. 649,554, dated. May15, 1900.

Application filed April 8, 1,899. Serial Nq. 712,294. (No model.)

.To ctZZ whom it may cow/carie: l

Beit known that I, FERDINAND ScHWED'r- MANN, a citizen of the UnitedStates of America, residing at St. Louis, in the State of Missouri, haveinvented a certain new and useful Electric Switch, of which thefollowing is such a full, clear, and exact description as will enableany one skilled in the art to which it appertains to make and use thesame, reference being had to the accompanying drawings, forming part ofthis specication.

lVIy invention relates more especially to that type of electric switchesknown as plungerswitches, in which the current is controlled bymanipulating ahandle to which is attached one or more cond uctors in theform of plungers and which are intended'for handling heavy currents.

One object of my invention is to so construct the switch that thepossibility of arcing will be reduced to a minimum.

Another object of my invention is to improve the construction of theswitch.

Another obj ect of my invention is to so construct the switch that noneof the current-carrying parts will be exposed, and thus protect theoperator from danger.

My invention consists in various novel fea* tures and details ofconstruction, all of which are described in the following specificationand pointed out in the claims affixed hereto.

In the accompanying`drawings,which illustrate a single-pole two-throwswitch made in accordance with my invention, Figure 1 is a sideelevation. Fig. 2 is a vertical central section. Fig. 3 is a top planview. Figs. 4. and 5 are views, on an enlarged scale, showing parts ofFig. 2; and Fig. 6 is a section, also on an enlarged scale, on the line6 6 of Fig. 2.

Like marks of reference refer to similar parts in the several views ofthe drawings.

10 is a slab of marble or other non-conducting material. Secured to theslab 10 are arms or brackets 11, carrying two smaller slabs 12 and 13,also preferably of marble.

15 represents hollow metal disks, two of which are attached to the lowerface of the slab 12 and two to the upper face of the slab 13. Carried bythe disks 15 and extending into openings in the slabs 12 and 13 aresplit metal tubes 16, surrounded by coil-springs 17. Held in the hollowdisks 15 by screwplugs 18 are carbon rings 19. Each of the rings 19isdivided into segments, preferably three in num-s ber, as shown in Fig.6. The segments of the rings 19 are forced toward the center bycoilsprings 20, held in projections 21 by screws 22. Formed on each ofthe hollow disks 15 is a plate 23, to which a suitable line-wireterminal may be secured. In each of the screwplugs 18 is a recess'inwhich rests one end of a tube 24., of lava or other refractorynon-conducting materal. Y

Passing through the slabsrlO, 12, and 13 and the disks 15 and tubes 24are two plungers 28. The centerof each of the plungers 28 is formed ofarod 29, of brass or other con-y ducting material. Rigidly secured oneach of the rods 29 is a collar 30, of copper or other con-k ductingmaterial. The collar 30 is of such a size as to it closely in the tubes16 and form with them connections, such as are described in LettersPatent No. 612,123, granted to me Octoberll, 1898. Placed around therods 29,

at each end of each of the collars 30, are

a carbon ring 31 and a ring 32, of some refractory non -conductingmaterial, such as vulcabeston, as best shown in Fig. v5. Any arc whichmay be formed in operating the switch will be formed between the carbonrings 31 and the spring-actuated rings 19, thus protecting the metalcontacts 16 and 30. The object of the vulcabeston rings 32 is to protectthe insulating-sleeves, hereinafter to'be described.

In a single-throw switch only one of the carbon rings 31 and one of thevulcabeston rings 32 would be necessary for each plunger, as only onepair of contacts 16 wouldY be f used.

Placed around the rods 29 are sleeves 33, preferably of fiber. Thesleeves 33 are of the same or substantially the same diameter as thecollars 30, so as to iill the tubes 16 coinpletely and exclude the airtherefrom. In order to make the insulation more perfect, I place a layer34C of mica between the rods 29 and the sleeves 33.

35 represents fiber stuffing-boxes, two of which are secured to theupper face of the slab 12 around the plungers 28 and two to the bottomof the slab 13 around said plungcrs. Each of the stuffing-boxes 35 isprovided with. a follower 36.

IOO

The object of the stuihng-boxes 35 and followers 36 is to moreeffectually exclude the air from the contacts, and thus aid inpreventing the formation of an arc.

On the lower end of each of the rods 29 is a nut 38, Fig. 2, which holdsthe lower sleeve in position and also supports a soft-rnbber washer 39,adapted to strike against the follower 36 of the lower stuffing-box 35and prevent jars when the switch is operated. The nuts 3S and ends ofthe rods 29 are protected by caps 40 of liber o r other insulatingmaterial.

Near the upper end of each of the rods 29 is a nut 42, which holds inplace the upper sleeve and a soft-rubber washer 43. Held between thenuts 42 and nuts 441s a strip 45, of copper or other good conductingmaterial, which forms an electrical connection between the cores 29 ofthe plungers 28. The strip 45 is covered by insulation 46, as shown inFig. 4. The nuts 42 and 44 are protected by j ack ets 47 of hard-rubberor other insulating material.

48 is a cross-bar which is held at each end between two washers 49,-preferably of liber, and which is kept out of contact with the rods 29by short sleeves 50, preferably of hard rubber. The washers 49 are heldin place by nuts 51, and the said nuts and the ends of the rods 29 areprotected by caps 52. The sleeves 50 and washers 49 keep the cross-bar4S out of contact with the metal parts of plunger 28, thus preventingany electrical communication between the handle, hereinafter to bedescribed, and the ernment-carrying parts of the switch.. Secured to thecross-bar 48 is a spadehandle 54, the grip 55 of which is preferably ofhard rubber or other insulating material.

The operation of my switch is as follows: XVhen the handle 54 is drawnupward, the copper collars 30 are drawn into the upper tubes 16, thusmaking good electrical connection therewith. one of the terminal strips28, through the disk l5,- tube 16, and collar 50, into the rod 29,thence up the rod 29, across the strip 45, down the other rod 29, andout through the other collar 30, tube 16, disk 15, and terminal strip23, thus completing' the upper circuit. To break the circuit, the handle54 is forced downward. This withdraws the collars 30 from the tubes 16at the same time the insulating-sleeves 33 are forced into the saidtubes, excluding the air therefrom, and thus preventing the liability ofthe formation of an arc. If, however, any slight are should be formed,it will be formed between the carbon rings 31 andthe segments 19. IfVhenthe handle 54 is forced to its lowest position, the collars SO areforced into the lower tubes 16. In this position the current Hows fromone ol. the lower terminal strips 23, through the lower disk 15 and tube16, into the sleeve 30, when it flows around, as previously described,to the other sleeve 30 and thence out through The current now passesfrom the other lower tube 16, disk 15, and terminal strip 23, completingthe lower circuit. The stuffing-boxes 35 and followers 36 aid inpreventing any air from entering around the plu ngers 2S. The handle 54being completely insulated from'the rods 29 of the plungers 28, theoperator of the switch is fully protected from any danger of a shock byoperating the switch.

YVhile I have shown a single-pole doublethrow switch, I wish it to beunderstood that I do not limit myself to such form of switch, as myinvention is applicable to either single or double throw switches andalso to switches having two or more poles.

Having fully described my invention, what I claim as new, an d desire tosecure by Letters Patent of the United States, is-

1. In an electric switch, a hollow contactpiece, a suitable rod ofconducting material passing longitudinally through said contactpiece, acylindrical piece of conducting material carried by said rod and adaptedto lit in said hollow contact, and an insulatingsleeve surrounding saidrod of conducting Inaterial at one end of said cylindrical piece ofconducting material and adapted to enter said contact when the circuitis broken and exclude the air therefrom.

2. In an electric switch, two hollow contacts, a plunger sliding in saidcontacts and having one part of its surface of conducting material andanother part o1' insulating 'material, a tube of refractory,non-conducting material arranged between said hollow contacts and intowhich the conducting-surface of said plunger passes when moving out ofeither of said hollow contacts, and means for excluding the air fromsaid tube of refractory, non-conducting material.

3. In an electric switch, a suitable hollow contact, a plunger passingthrough said contact, a metallic cylinder carried by said plunger andadapted to fit in said contact, an insulating-sleeve also carried bysaid plunger and adapted to fit in said contact, a carbon ring betweensaid sleeve and said cylinder,- and a spring-actuated carbon ringcarried by said contact.

4. In an electric switch, a plunger having one part of its surface ofconducting material and another part of insulating material, a passagein which said plunger slides, a part of the walls of said passage beingof: conducting material and adapted to make contact with theconducting-surface4 of said plunger, and a packing at the ends of saidpassage for permanently maintaining air-tight joints around said plungerand excluding the air from said passage.

5. In an elect-ric switch, a suitable hollow contact, a plunger adaptedto pass through said contact, a metallic cylinder carried by saidplunger and adapted to lit said contact, an insulating-sleeve alsocarried by said plunger and adapted to .nt said contact, and a IOO IIO

stuffing-box and follower at each side of said contact and around saidplunger to exclude the air from said contact.

6. In an electric switch, two plungers each having a core of conductingmaterial, suitable contacts cooperating with said plungers to make andbreak the circuit, a connectingstrip of conducting material for saidplurigers, a cross-bar secured to the cores of said plungers butinsulated therefrom by sleeves of non-conducting material, washers ofnonconducting materialbetween which said crossbar is held, and a handlesecured to said cross-bar for actuating said plungers. l

. In testimony whereof I have hereunto set I5 my hand and aixed my sealin the presence of the two subscribing witnesses.

n FERDINAND SCHWEDTMANN.

Witnesses:

W. A. ALEXANDER, C. D. GREENE, Jr.

